Second Crusade

The Second Crusade occurred from 1147 to 1150 when 20,000 German soldiers under Holy Roman Emperor Conrad III and 15,000 French troops under King Louis VII of France marched into Anatolia and the Levant with orders from Pope Eugene III to recapture the County of Edessa, which had fallen to the Turkish warlord Imad ad-Din Zengi in 1144. The crusade failed to recapture Edessa, as the crusaders unwisely dragged Zengi's rival Muslim state of Damascus into the conflict during a failed siege of the city in 1148. However, an army of 13,000 Flemish, Frisian, Norman, English, Scottish, and German crusaders en route to the Holy Land assisted Portugal and the Spanish kingdoms of Castile and Leon in capturing Lisbon from the Almoravids in 1147, the only Crusader success during the Second Crusade.

Gallery
In the aftermath of the First Crusade in 1099, the four crusader states (the Kingdom of Jerusalem, the Principality of Antioch, the County of Edessa, and the County of Tripoli) continued to fight against the neighboring Muslim states for control of the Levant. The Holy Lands were subjected to frequent attacks by the neighboring Seljuk Turkish warlords over the next several decades. In 1128, the Turkish warlord Imad ad-Din Zengi conquered the Syrian city of Aleppo, and he failed to capture Damascus in both 1139 and 1140. In 1144, Joscelin II of Edessa allied with the Turkish Artuqids in an attempt to halt the Zengids' expansionism, but Zengi besieged Edessa, which fell on 24 December 1144. Joscelin fled to Turbessel, and the rest of Edessa was gradually overwhelmed by the Zengids. Zengi was assassinated by a slave in 1146, but his son, the equally-capable Nur ad-Din, succeeded him. Meanwhile, Pope Eugene III called for another crusade to reclaim Edessa from the Saracens, and he sought for the strongest kings of Europe to lead the crusade. On 1 March 1146, Pope Eugene had Bernard of Clairvaux preach the crusade throughout Europe, and an army of 35,000 German and French crusaders led by Conrad III of Germany and Louis VII of France was assembled to relieve the Holy Lands.

Iberian Peninsula
In 1147, the Pope authorized the expansion of the Second Crusade into the Iberian Peninsula as part of the Reconquista. A fleet of 13,000 German and British Isles crusaders en route to the Holy Land was forced to disembark at Porto, Portugal on 16 June 1147 due to a storm, and King Afonso Henriques recruited them to assist him in capturing the major city of Lisbon from the Almoravids. From 1 July to 25 October 1147, Lisbon was besieged by the Crusader army, and the defenders were starved into surrendering. Many of the crusaders settled in Lisbon and then helped to liberate Santarem, Sintra, Almada, Palmela, and Setúbal; they were then allowed to live in the conquered lands, marry, and have offspring. In October 1147, Almeria fell to a Catalan, Leonese, Castilian, Italian, and French fleet. In December 1148, Ramon Berenguer IV of Barcelona went on to capture Tortosa, and, in 1149, he captured Fraga, Lleida, and Mequinenza.

War in the Holy Lands
In May 1147, the German and French crusader armies set out for the Holy Lands, and King Geza II of Hungary allowed the crusaders to pass through his lands unharmed, while Emperor Manuel II of Byzantium had Byzantine troops deployed to ensure that the Crusaders did not attack his lands. However, the divide between the Catholic crusaders and the Orthodox Christian Byzantines was felt when Roger II of Sicily led his army to plunder Greece, while the German crusaders engaged in large-scale clashes with Byzantine troops within Constantinople before Conrad III decided to hastily resume the march into Asia Minor. Manuel had the crusaders swear to return any territory they had captured, following the same policy as his grandfather Alexius I of Byzantium during the First Crusade.

In July 1147, the crusader forces assembled at Tiberias, where their numbers swelled to 50,000. They decided to attack the Muslim state of Damascus, which was rivals with the Zengids, but which was much weaker, and which would prove to be a vital base for further campaigns against Zengi. Rather than ally with Damascus against the Zengids, the crusaders instead besieged the city in July 1148. The Damascenes reluctantly allied with Nur ad-Din and the ruler of Mosul, Saif ad-Din Ghazi I, and the crusaders were forced to retreat, being harried by Turkish archers as they withdrew. The failure to take Damascus and the withdrawal of the Crusader forces effectively ended the crusade, as the crusader kings began to squabble among each other. Conrad immediately returned to Constantinople to further his alliance with Manuel, while Louis returned to France in 1149.

Aftermath
The Second Crusade failed to reclaim Edessa for the crusaders, and Nur ad-Din conquered Damascus in 1154. Meanwhile, Baldwin III of Jerusalem seized Ascalon from the Fatimid Caliphate of Egypt in 1153, and Egypt was again brought back into the sphere of conflict. From 1149 to 1187, the Crusader states would continue to fight against Muslim incursions, and the fall of Jerusalem to the Ayyubid ruler of Egypt, Saladin, in 1187 led to the Third Crusade shortly after.